1. Field of the Invention
This invention relates to a server unit, a client unit, a server-based computing system, a server control method, a client control method, a server control program, and a client control program in a server-based computing (SBC) system which causes the server unit to activate and execute a desired application program in response to a remote operation at the client unit in a client-server system.
2. Description of the Related Art
In the SBC system, a key output signal, a mouse output signal, or the like corresponding to the user operation on a client unit is generally transmitted as an event signal to a server unit each time the signal is generated. Then, the server unit runs an application program corresponding to the event signal from the client unit and transfers the resulting drawing data to the client unit each time the drawing is updated, thereby causing the client unit to display the drawing data.
As described above, in the SBC system, each time the user operates the client unit, the event signal generated at that time is transmitted to the server units. For this reason, in the server unit which processes the event signals from many client units, the burden of processing the event signals increases, which decreases the operation response when viewed from the client unit.
A conventional SBC system is such that, in a communication between a server unit and a client unit, commands are defined in graphical user interface (GUI) components and the property value of a GUI component and a command representing the user operation for the GUI component are transmitted, thereby reducing the amount of communication data and realizing a fast GUI response (e.g., Jpn. Pat. Appln. KOKAI Publication No. 2005-228227).
In recent years, mobile terminals have been used widely as client units of the SBC system. Since the key input unit of the mobile terminal is provided in a small space, the types of keys are restricted. Accordingly, in a case where the server unit gets various programs running according to an input event corresponding to the user operation, when a frequently used command, such as “Favorites”, “Back” or “Forward” in a Web browser program or “New”, “Save” or “Undo” in a text creation program, is input, the command cannot be input by a key operation and has to be input only by specifying the shortcut for each command displayed on the display screen with a pointer and pressing the enter key.
Consequently, this causes a problem: a pointer operation on the small display screen of a mobile terminal is particularly difficult to understand, troublesome, and liable to be erroneous.